Text Size:   A+ A- A   •   Text Only
Site Image

OR 43: Oregon City/West Linn Arch Bridge

Project Summary:

The historic Oregon City/West Linn Arch Bridge spanning the Willamette River has been a source of community pride since its opening in December 1922. However, after more than 90 years, this famous old bridge needed repairs.  Throughout the bridge, the deck, joints, rails, lighting and protective coating of the arch span required repair and replacement.
Work on the bridge began in summer 2010.  To protect the safety of all, the narrow bridge was closed until October 15, 2012.  Vehicles were detoured over the nearby I-205 Abernethy Bridge.  A shuttle service accommodated bicycle and pedestrian travel during the closure.  The bridge is now open to traffic.  Some work will continue through January 2013 when the final signs are installed. 

Latest Information:
(as of January 2013) 

Oregon City/West Linn Bridge Rehabilitation Update 

Project  Update  January 2013 
This is the final project update for the Oregon City/West Linn Arch Bridge Rehabilitation Project.
ODOT is proud to have restored the bridge to its original grandeur for the use and enjoyment of the communities for years to come.  We want to thank you, again for your patience during this project. 
Also, we want to share some interesting statistics provided by the contractor, Wildish Standard Paving, to illustrate the work done on the project. 
The project is 99.99% complete and will finish ahead of the final contract date of March 31, 2013. In addition, the reopening of the bridge to traffic was on-time after the 21-month closure. 
On December 20, the replica lights were re-installed.  They had been sent back to the manufacturer to increase their weather resistance.  After the re-installation, the lights were left on for a 7-day "burn-in" (24/7) test.  We have received lots of positive comments from local residents who were happy to see the lights back on.   
The only item remaining to be completed is the installation of some small signs which will occur in late January.  There will be no further impact to bicycle, motor or pedestrian traffic.   
The Contractor and the Project
Wildish Standard Paving is proud of their safety record on this project.  There was no time lost to injuries during 61,000 hours of labor. 
This project employed a work force of carpenters, steel workers, concrete finishers, equipment operators, truck drivers, painters, welders, electricians, tug boat operators, steel fabricators, concrete precast fabricators, sign fabricators, concrete suppliers, asphalt suppliers, materials testing technicians, project inspectors, engineers, structural engineers, traffic engineers, shuttle bus drivers along with other laborers and a variety of other project related staff. 
·         Final estimated project construction cost - $14,904,000. 
·         The total construction work lasted 35 months, from its start in July 2010 until final close-out in the spring of 2013.  For nine months, Wildish employees worked double shifts, in order to finish the project on time.  There were up to 40 people working at one time including the subcontractors.  The nature of the work and tight spaces precluded more workers on the bridge at any one time. 
·         The total project utilized 61,000 hours of labor.
·         The painting of the bridge both inside and outside took 7,200 hours of labor. 
·         The historic replica lights on the bridge were patterned after one of the original fixtures was found on Atkinson Memorial Church in Oregon City. It is thought they were removed from the bridge in the mid 20th century.
Gunite Removal
·         On the steel arches, 18,000 square feet of old Gunite was removed and replaced.
·         The contractor purchased special hydroblasting equipment for Gunite removal and used a variety of techniques to remove it.  Around 6,000 hours was spent removing Gunite.
·         400,000 pound per square inch of water pressure was required to blast off the old Gunite from the bridge. More than a million gallons of waste water was collected, cleaned and treated on the project from various aspects of hydroblasting including deck removal and bridge cleaning.
·         More than 7 barges, 3 tug boats and diving services were used preventing debris from falling into the river.
·         Johnson Western Gunite Company worked about 7,200 hours to apply the new shotcrete. 
Concrete and Steel Repair
·         More than 1,000 square feet of concrete were repaired. 
·         Approximately 350 cubic yards of concrete were replaced on the bridge rail, bridge deck, sidewalks and columns. 
·         Railing:  Over 1,600 linear feet of new precast concrete, steel reinforced railing were installed.Over 1,000 bolts were replaced.
·         540 corroded rivets were replaced with 3/4" diameter high strength bolts
·         Approximately. 30,000 pounds of structural steel were removed and replaced. Structural steel is a steel beam, column, plate used to support the bridge loads.
·         Approximately 54,000 pounds of new reinforcing steel were used.  Reinforcing steel or rebar are rods of steel embedded in concrete to give the concrete flexibility. 
·         Below the bridge deck—8 steel bridge stringers were replaced, due to corrosion.  Stringers are the support beams that run the length of the bridge.  In addition, 32 stringers, with less corrosion, only needed repair.
·         Bridge Roadway—A micro silica concrete deck overlay was installed.  This is structural concrete that is less permeable to water and therefore reduces the potential for future corrosion of the steel under the bridge deck.   
·         Installed steel seismic cables under the West Linn and Oregon approaches to the bridge, tying the bridge deck’s super structure to top of the columns. 
·         The bridge supports a natural gas line, communications lines and the sanitary sewer line that go between Oregon City and West Linn. These services had to be maintained during the rehabilitation project.   Some of the lines were moved to enhance the historic features and to make these lines less visible. 
Facts for engineers and construction geeks
·         We installed 2,200 galvanic anodes, or sacrificial anodes, to help avoid future steel corrosion of bridge members and rebar.  This is like you might install on your outboard boat motor. They are a small piece of zinc metal that is about the size of a deck of cards.  This is electrically connected by wires to rebar or other bridge steel.  This is a sacrificial piece of metal that will corrode before the bridge steel corrodes.
·         Teflon sheets were installed between the bridge girder bearing surfaces. Girders are similar to stringers but span between the columns.  The girders sit on top of cross beams that sit on top of the columns.  A Teflon sheet was placed between the girder and cross beam to help allow girder to expand and contract with hot and cold temperatures while column stays stationary.
Ribbon Cutting and Arch Bridge Opening Ceremony
The Oct. 14 bridge opening event included brief speeches by ODOT Director Matt Garrett, the Mayors of Oregon City and West Linn, representatives from the Federal Highway Administration and Wildish Standard Paving, the construction firm. Two time capsules, containing items of from the Cities of Oregon City and West Linn, were dedicated. Music was provided by the Willamette Falls Symphony Brass Ensemble. 
A parade of historic cars from 1915 to 1932 were the first vehicles across the restored bridge carrying the dignitaries.  The parade will also include bicyclists and pedestrians who have been riders on the Bridge Shuttle. 

The Willamette Falls Festival and its sponsors provided fireworks to celebrate the Arch Bridge reopening.

ODOT Director Matt Garrett thanks the community for its patience and cooperation during the restoration of a historic bridge and Oregon treasure.

Ribbon Cutting Opens the Bridge.  From left, Tim Hendrix of Wildish, Matt Garrett, ODOT Director, Oregon City Mayor Neeley. West Linn Mayor Kovash, Jason Tell ODOT Region Manager and Clackamas County Chair Charlotte Lehan.
Bridge Shuttle Service ended October 14

With the opening of the Oregon City/West Linn Arch Bridge in the early morning hours of October 15, the need for the Bridge Shuttle ended. 

The Shuttle carried 68,129 riders including 12,291 bicyclists in its 21 months of operation.

First Student of West Linn and its drivers have done an excellent job.  Their drivers provide superior customer service, and we have received many, many compliments from riders.  ODOT extends a sincere thank you to First Student for a job well done. 

Partnerships and Cooperation
ODOT worked closely with the cities of Oregon City and West Linn, Clackamas County and Historic Downtown Oregon City throughout the development of this project. 

Many thanks from ODOT to the local businesses, especially in downtown Oregon City for their feedback, patience and cooperation during the bridge construction.

Susan Hanson, Community Affairs Coordinator, ODOT

Read archived project updates (March 2009 - November 2012)


Project Information

/ODOT/HWY/REGION1/or43_willamette_river_br/currentbridge.jpgThe Oregon City/West Linn Arch Bridge on Oregon Highway 43 opened on Jan. 1, 1923.  This bridge has served the communities well for 89 years.  More than 13,500 vehicles and 200-300 bicyclists and walkers cross the bridge each day.  Inspections have revealed some corrosion of the underlying steel structure, damaged railings and the need for resurfacing the bridge deck and the Oregon City approach.
This bridge and many other beautiful Oregon bridges are the legacy of Conde B. McCullough, who was considered one of the top bridge engineers in the world.  He designed more than 30 arches bridges in Oregon at a time when travel by automobile was not common.  This project is an opportunity to restore this one-of-a-kind bridge and maintain the significant link between Oregon City and West Linn.
When the project is complete, this architectural treasure will be restored and its life-span extended to serve the community for years to come.

Read Frequently Asked Questions about the bridge project.

Traffic Impacts
History of the Bridge
/ODOT/HWY/REGION1/or43_willamette_river_br/oregoncitydetourmap.jpgThis historic bridge linking Oregon City with West Linn was officially opened on Jan. 1, 1923. It was designed by Conde McCullough, the Oregon State bridge engineer who is primarily known for building many of Oregon’s coastal bridges on U.S. Highway 101.
Before McCullough built this bridge, an old wooden suspension bridge constructed in 1888 connected both sides of the river.  The old bridge, however, could not carry the additional traffic expected with the new Pacific Highway (Oregon Highway 99E). 
McCullough studied this location for two years trying to determine what type of bridge would work.  A steel arch, in which the roadway is support partway up the arch, was what he finally chose.  McCullough had constructed many arch bridges for Oregon’s highways.  However, this bridge was his first where the roadway was not on top of the arch or below the arch but in-between.
The roadway is supported between two massive 350-foot arch ribs.  Each arch rib is actually a series of individual hollow steel boxes end to end.  McCullough used the old suspension bridge to support the individual boxes as they were being connected.  Once all of the arch boxes were put together, he built the columns that hold the roadway up and the hangers that suspend the roadway from above.  Finally, he installed the beams that directly supported the roadway. 

To prevent rusting, he encased the exposed steel members in a concrete covering called Gunite.  Gunite was a combination of sand and cement that was mixed with water.  This mixture was blown by compressed air onto the steel surfaces.  Gunite was used instead of paint to protect the steel in the 1920s from the corrosive atmosphere generated by nearby mills. Today, the mills do not generate corrosive fumes but the bridge will be restored to its original appearance with a shotcrete coating.   
In 2005, the bridge was listed on the National Register of Historic Places and is likely the only one of its type in the world.
Click here to view more historical photos of the bridge.

ODOT Contact Information
Susan Hanson, ODOT Community Affairs Coordinator
(503) 731-3490